Gravity or pumped cylinder

[Ubarrow]

I have a hot water system that has been fed by an Aga. It's always been a bit slow to warm up.
Now the Aga is going and I'm altering the system so that the oil boiler heats the hot water via an indirect cylinder, vented system.
I'm just wondering if the hot water cylinder is actually fitted with a "gravity or pumped" designed coil. Obviously if the wrong one was originally fitted then it would explain the poor performance of the Aga and also mean I don't have to buy a new cylinder.
Is there any way to tell?

 

[Dan Robinson]

It is an irrelevance of you are moving to fully pumped.

 

[Ubarrow]

I understood that the coils were different and that the coils in a gravity tank were larges and would not be as efficient in a pumped system?

 

[45yearsagasman]

These days, why would you even consider gravity circulation? Fully pump your system.

 

[Ubarrow]

Sorry, perhaps I wasn't clear. I'm moving to a fully pumped system fed from the existing oil boiler. The previous system was in fact 2 independent systems, one gravity fed from the Aga and one pumped system from the oil boiler. I'm converting to an S plan system. But my question is about the hot water tank. How can I tell whether or not it is designed for gravity or pumped circulation?
Clearly it should be one designed for gravity circulation and therefore need replacing but I'd just like to check before shelling out.
The poor performance of this old gravity system makes me wonder if the wrong one was fitted.

 

[Richardthe3rd]

All depends, the AGA may require gravity circulation.

 

[Dan Robinson]

Why does it need replacing?


Just Crack on.

The only issue might be if you are sealing the system.

 

[Ubarrow]

The Aga is going!

I'm putting in a fully pumped system and wondering whether I need to replace the hot water cylinder

My question is simply: How can I tell whether a hot water cylinder was designed for use with a gravity system or a fully pumped system. I believe that they are different and that using the wrong one will lead to poor performance

 

[Dan Robinson]

Flirking Nora.

 

[JohnD]

What colour is your old cylinder, and what is printed on it?

Does it seem big enough for your needs?

 

[pallen5000]

The existing cylinder probably will have a coil, or it could be Primatic. I'm not 100% sure but I think you can have primatic fully pumped but the pump may need to be fitted different way. (I may be corrected) but if it was primatic I would probably change it.

 

[Ubarrow]

What colour is your old cylinder, and what is printed on it?

Does it seem big enough for your needs?

Its yellow and marked indirect in felt tip pen. Can't find any other marks on it without taking it out.

Size is ok.

Presumably the fittings are the same size and position, whichever system it's designed for.

Clearly it will work in a fully pumped system, the manufacturers of cylinders all tell you it's important to use the correct one and I guess that using one designed for a gravity system in a pumped one is better than the other way round.

 

[D_Hailsham]

Its yellow and marked indirect in felt tip pen.

It will work OK, but modern cylinders are much better insulated than your yellow foam covered one. So it might be worth considering a new one as it will retain heat much longer

A new cylinder will also heat up much faster, so you may not need such a large one.